Dr Baumgarten analyses three possible justifications for doctors to decide that a patient is 'incompetent' to make or participate in medical decisions affecting him, and points out the difficulties of each. He argues that the degree to which a patient relinquishes control over decision-making which affects him will vary in different circumstances and should be explicitly agreed in the initial doctor-patient contract, rather as it often is when a client employs a professional to invest money on his behalf